The actresses playing Aster (Sophie Nélisse) and Talulah (Abigail Pniowsky) previously played sisters in Wait Till Helen Comes (2016).
In the 34th minute the store cashier in the red shirt has the logo of Canadian chain store Home Hardware on his red shirt. The name tag below the logo just says 'Home' and his name, but he is clearly wearing a uniform shirt from the well-known Canadian hardware chain.
The book that Aster is reading after the funeral is "Helter Skelter: The True Story of The Manson Murders" (1974). It is the story of the Hinman, Tate, LaBianca, and Sheah murders, written by Charles Manson prosecutor Vincent Bugliosi and Curt Gentry. Besides the obvious connotations with the Aster character, it is significant that it is the full-size hardback edition with book jacket. This would only be found in a very large library or from one's private library. By far, the paperback edition was much more common, so this edition emphasizes Aster's mindset.